Mobile apparatus for working on roadways or the like



Oct. 20, 1953 H. B. KEOGH 2,655,678

MOBILE APPARATUS FOR WORKING ON ROADWAYS OR THE LIKE Filed July 1, 1949 2 Sheets-Sheet l H. B. KEOGH 3 MOBILE APPARATUS FOR WORKING ON ROADWAYS OR THE LIKE Filed July 1, 1949 2 Sheets-Sheet 2 Patented Oct. 20, 1953 MOBILE APPARATUS FOR WORKING ON ROADWAYS OR THE LIKE Hedley Benjamin Keogh, Thornbury, Victoria, Australia Application July 1, 1949, Serial No. 102,633 In Australia July 20, 1948 13 Claims.

This invention relates to mobile tools, devices or apparatus that require to work or operate at a required distance from or directly upon a work surface, such as a roadway or the like.

For instance road grading, sweeping or cleaning apparatus or machines for removing rubbish or leaves require to be controlled to accurately traverse the particular roadway, channel or surfollow the contour of and operate upon the area within the cavity or depression.

With the above stated objective in view there is provided according to this invention a mobile apparatus for working on roadways or the like, comprising means to automatically control the surface-engaging member of the apparatus, and comp-rising a pilot means so connected with the surface-engaging member that responsive to changes in contour, irregularity or to obstructions on the surface, the surface-engaging member is automatically moved to conform with the contour or clear the obstructions.

Thus the surface-engaging member such as a brush, broom or grading member, is automatical- 1y controlled to follow very closely the surface whereby undula-tory portions or holes are operated upon by the surface-engaging member which incidentally is resultan-tly maintained at the required operative position relatively to the surface.

In one embodiment of the invention applied to a street sweeper, or suction device for picking up leaves or rubbish, the particular member is mounted for vertical movement relatively to the ground, a pilot wheel or the like is mounted in advance of the member, and with the latter operatively connected to valvular means controlling a source of fluid pressure, and means operable in response to the fluid pressure are connected to the member for moving the latter relatively to the surface. Thus movements of the pilot wheel or the like resultant upon close tracking upon the surface are translated to the valvular :means whereby the above member is automati- .2 cally moved i. e. raised or lowered or angulafiy moved a proportional distance whereby it will also follow closely the contour ofthe surface irrespective of irregularities mr imdulatory sections in the latter.

The invention will be better understood from the description/or the practical arrangement of a control means or apparatus for the rotary broornof a street sweeper illustrated in the accompanyin drawings.

In these drawings: Fig. 1 is a front elevation, somewhat schematic of the control means or apparatus, showing the rotary broom and part of the frame of the street sweeper.

Fig. 2 is a view in plan on the line 2-2 of Fig. 1.

Fig. 3 is a side elevation, partly schematic, of the control means or apparatus illustrated by Fig. 1.

Fig. 3a is a transverse section of rotary valvular means operable by pilot means to control the actions of the apparatus.

Fig. 4 is a sectional detail of a pivotal support and an adjustable bearing in the power transmission means operating the rotary broom.

Fig. 5 is a schematic sectional view of a modified valvular means controllin the operation of a booster or servomotor for raising and lowering the rotary broom, together with manual means and automatic means for actuating the valvular means.

Fig. 6 is a transverse section or modified valvular control means.

Fig. '7 is a longitudinal section of a further modified valvular control means.

Referring to the drawings, the numeral l0, designates a side or longitudinal member of the frame or chassis of the road sweeper which is power motivated and of any suitable or approved construction.

Secured, as for instance by welding, to the member Ill, are spaced brackets H, to which is pivotally connected in a manner hereinafter explained, a tubular arm l2 which depends from the brackets ll and is reinforced by an integral web l3.

To the lower end of the arm 12 there is secured at right angles, a flange [4 having integral therewith spaced plates 15, which together with the flange comprise a bifurcated or forked structure l 6 at the lower end of the arm l-2.

'Pivotally connected to the bifurcated structure IS in a similar manner to the arm 12, and as described :later herein, is a tubular :arm ll similarly reinforced to the former arm and having at the opposite end a similar bifurcated structure clearly seen in Fig. 2. The arm I2 may be termed the primary arm, while the arm I1 may be hereinafter referred to as the secondary arm.

The bifurcated structure I8 has spaced sides or plates I9 between which is supported a gear box 28 by pivots or trunnions 2I integral with the latter and journalled in coaxially aligned apertures in the plates I9.

Rotatably supported by the gear box 23 is a rotary broom 22 which is power-driven by a power take-off on the machine or by a separate or auxiliary motor thereon, if required.

It will be observed and understood from an inspection of Fig. 1, that the primary tubular arm I2 may be angularly moved about the pivotal axis thereof on the brackets II, so as to adjust the rotary broom 22 to a position at a greater or less distance from the side of the road sweeping machine, and to extend the broom laterally therefrom or retract the latter inwardly thereto.

Moreover, it will be apparent that the rotary broom may be 'raised and lowered by angular movement of the secondary arm I1 about the pivotal axis thereof on the bifurcated structure I6 at the lower end of the arm I2.

Furthermore, it will be apparent that the rotary broom may be inclinably adjusted as indicated by chain lines in a transverse plane substantially at right angles to the machine by angular movement of the gear box 28 in the bifurcated structure I8 at the end of the secondary arm I1.

For the purpose of driving the rotary broom 2 I, shaft 23 is rotatably supported in bearings, later described, in the spaced brackets II and is operatively connected with rotary driving means (not shown) actuated by the power-take-off or the auxiliary motor, and provided with a clutch or the like, whereby the broom may be operated by or disconnected from the power drive at the will of the operative.

Secured to the shaft 23 is a sprocket 24 which by a chain 25 is operatively connected with a sprocket 25 secured to a shaft 21 extending through and rotatably supported by bearings, later described, carried by the side plates I of the fork or bifurcated structure I6.

Upon the opposite end of the shaft 21, there secured a sprocket 28 which is drive-connected by a chain 29 with a sprocket 30 secured to a shaft 3| which is rotatably supported in and extends axially through the trunnion 2I into the interior of the gear box 20.

The broom 22 is secured to a shaft 32 rotatably mounted in the gear box at right angles to the shaft 3! which is drive connected with the shaft as by bevel gears enclosed within the gear box.

It will be apparent that a driving torque applied to the shaft 23 will be transmitted through the sprocket 24, chain 25 and sprocket 26 to the shaft 21, and thence through the medium of the sprocket 23, chain 29 and sprocket 30 to gear box shaft 3| and via the gears enclosed within the gear box to the shaft 32 and broom 22 which accordingly is rotated.

It will further be apparent that the centre distances of the shafts 23 and 21 and of the It is however, necessary to provide means for latter shaft and the shaft 3| are constant and unaffected by the articular movements of the arms I2 and I1, so that the rotation of the rotary broom is continuous, notwithstanding the relative angular movements of the arms.

.4 adjusting the distance between the shafts 23 and 21 and between the latter shaft and the shaft 3I, to take up wear and prevent undue slackness developing in the chains 25 and 29. It is moreover, necessary to take up Wear of the pivotal joints or bearings of the arms I2 and I1 to maintain rigidity and prevent the development of endwise slog and shake with resultant wear.

In order to meet these adjustment requirements, there is provided a special adjustable pivotal connection for the arm I2 with the brackets II and for the arms I2 and I1 with each other, which also embodies an adjustable bearing for the shafts 23 and 21.

Referring to Fig. 4 illustrating the special connection as used for associating the arms I2 and i1 and rotatably supporting the shaft 21, the arm [1 has integrally fixed thereto, as by welding, a bearing housing 33, the opposite ends of which are bored to receive bearing bushings 34 tapered internally to fit conical supports 35 comprising coaxially aligned pivots whereon the housing 33 and the arm I1 are angularly movable.

The pivotal supports 35 have cylindrical portions 36 adjustably rotatable in coaxially aligned apertures 31 in the spaced plates I5 of the bifurcated structure I6 at the lower end of the arm I2.

Flanges 38 on the pivotal supports 35 are apertured at spaced intervals to receive screws 33 whereby the pivotal supports are fixed to the plates I5, shi'ns or thin plates 40 being interposed between the flanges 38 and the plates I5 and being removed as required for taking up wear of the cones 3-5 and tapered bushings 34, whereby the pivotal connection of the arms I2 and I1 may be maintained firm and flexible and yet free from shake as necessary for efficient operation.

The pivotal supports 35 also provide adjustment for the shaft 21 to take up slackness and wear in the chain 29.

For this purpose, the shaft 21 is rotatably supported in bearings III mounted eccentricaily in the pivotal supports 35, so as to locate the axis of the shaft 21 radially outward from and parallel with the common axis of the former.

It will be apparent that adjustable rotation of the pivotal supports in the apertures 31 will displace the shaft 21 bodily, thereby enabling slackness in the chain 29 to be readily take up.

The similar pivotal support associating the arm I2 with the brackets II, enables the former to be maintained free of shake and the shaft 23 to be displaced bodily to adjust the chain 25.

To enable the adjustment of the chains 25 and 28 to be maintained, the plates I5 and brackets I I are provided with spaced tapped holes 42 disposed in annular arrangement, the screws 39 being engaged with appropriate holes after each adjustment.

In order that the broom 22 in traversing a road surface may be adapted to rise and fall in conformity with the contour of the surface and be elevated to clear and pass over obstructions on the roadway, advantage is taken of the articular movements of the arms I2 and I1, particularly of the secondary arm I1 in moving angularly in a vertical plane about the pivotal connection at the lower end of the primary arm I2, as previously described.

For the purpose of automatically effecting the raising and lowering of the broom 22, there is provided a pilot wheel 43 which leads or travels in advance of the broom nd encounters a change of contour .or an obstruction prior to cf the broom thereat or contact therewith- The pilot wheel is adapted to follow .a change of contour and to pass over an obstruction and its rising and falling movements in so doing, are utilized to efiect corresponding movements of the broom 22.

To provide for such movements, the pilot wheel '43 is carried by a frame indicated generally by 44 and comprised of pair of arms 45 and 46. which extend forwardly of the broom 2,2 and at the rear ends are pivotally connected to brackets 41-48 secured, as by welding, to the secondary arm.

At the forward ends the arms 45 and 46 are pivotally connected to a bracket 49 carrying a vertically disposed bearing 56 in which is rotatable the shank or spindle 5| of caster arms 52 connected together by a bolt 53 whereon the pilot wheel is journalled. Accordingly, the pilot wheel 43 is free to swivel about the bearing and track truly with the line of travel.

It will be seen that the pair of arms 45 are of approximately equal. length, as are also the pairs of arms 46, and that the latter pair of arms, although longer, have the same eifective length as the former pair of arms.

Accordingly, the arms 45 and 46 in swinging about the respective pivots provide a parallel movement for the bearing 50 which is maintained substantially upright as the wheel 43 rises and falls in traversing a roadway, see Figs. 3 and 5.

The vertically dis-posed movements of the pilot wheel 43 are utilized to control the actions of a pneumatic motor or vacuum booster 54 of well known construction, which is suspended by a link 55, pivotally connected at the upper end to lugs 56 on a plate 51 welded to the depending arm 12.

The vacuum booster .54 is as usual separated into an upper chamber and a lower chamber by a transverse diaphragm having fixed thereto the operative rod 58 which at the lower end is flexibly connected by chain links 59 to a lug 60 welded to the secondary arm H.

The lower chamber is at all times open to the atmosphere, and it will be understood that upon creation of vacuum in the upper chamber the diaphragm will be deflected to draw the rod 58 upwardly and thereby elevate the arm I! and D Fig. 3), whereby the booster may be connected with .a source of vacuum, or with the atmosphere, as and when required.

The control valve 6| comprises .a casing 52, which is cylindrically bored to have closely fitted therein a rotary valve 63.

The casing 62 has formed therein a. vacuum port 64 in constant communication by a flexible tube 65 with the vacuum source, and a service port 66 connected by a flexible tube 61 with the upper chamber of the vacuum booster 54.

In the periphery of the rotary valve 63 there is a groove 68 in communication with the vacuum port 64, and snugly fitted in a recess 69 in the rotary valve is a valve block 10, which as shown in Fig. 3, is closing the service port '66., thereby completely shutting oif communication of the upper chamber of the booster 54 both with the source of vacuum and the atmosphere.

Also formed in the valve block 10 is a recess .1] which as shown in Fig- 3,. is in communication with the atmosphere .by way of a passage 1.2 in the valve casing 62.

In order that the .rotary'valve 63 may be an larly moved in the casing 62 in response to the rising and falling of the pilot, wheel 43, the lower of the pairs of arms 45 and 46 are rigidly secured to a shaft 13 J'ournaled in the brackets 41-48 and fixed firmly to the rotary valve 63.

The valve casing 162 i rotatable upon and about the rotary valve .63, but .is normally restrained against movement by an anchorage member 14 which is adjustable for a purp pr s ntly xplained, and may conveniently comprise a flexible cable 75 connected to a manually operable handle 16 accessible from the drivers position.

In traversing a roadway, and assuming that the pilot wheel 43 encounters a change of contour of the road surface, such a an incline or up grade, or contacts with an obstacle on the roadway, and accordingly rises, the arms 45--46 will be moved angularly upwards and resultantly .the valve 63 will be rotated proportionally in clock- Wise direction, thereby moving the valve block 10 so as to connect the service port 66 with the groove 68 and vacuum port 64.

Accordingly, communication is made via the flexible tube 61 with the booster, so that a vacuum is created in the upper chamber and the operative rod 58 is drawn upwardly, thereby raising the broom 22 to negotiate the change of contour or clear the obstacle.

As the broom assembly rises, the pilot wheel remains on the road surface, and the upward movement of the valve casing 62 in rising with the broom assembly effects a relative anti-clockwise movement of the rotary valve 63 within the casing, so that valve block it shuts off communication of the service port 66 with the vacuum port 64 and thus arrests the upward movement.

Upon the pilot wheel 43 meeting with a depression or a down grade in the roadway, the resultant lowering of the arms 45 and 45 affects an anti-clockwise movement of the rotary valve 63, and the recess H in the valve block 1e connects the service port 66 and the upper chamber of the booster with the atmosphere by way of the passage 12, thereupon the broom assembly descends to a position at which the valve block 10 closes the passage.

To compensate for excessive bristle wear, which necessitates lowering of the rotary broom for effective surface engagement, the operative by actuating the handle 16 angularly adjusts the valve casing 62 about the rotary valve 65 in a clockwise direction, thereby connecting the service port 66 via the recess H with the passage 72 and the upper chamber of the booster with the atmosphere.

Thereupon the broom assembly descends and in so doing, effects a clockwise rotation of the shaft 13 and the valve 63 which eventually closes the service port 66, thereby terminating the downward movement.

If the rotary broom 22 bears too heavily upon the road surface, it can be raised, while the pilot wheel 43 remains on the surface, by rotating the casing 62 in an anti-clockwise direction by appropriate manipulation of the handle 16 by the driver of the machine.

In the modified valve and operating means illustrated by Fig. 5, the valve block To is influenced by a spring 1.! into close contact with the periphery of the valve casing 62, thereby effectively sealing the recess H which by a passage IB is in constant communication with the atmosphere by way of an axial passage I9 in the rotary valve 63.

This modified valve has an advantage in that the vacuum groove 68 is always separated from the recess H by the portion to of the valve block I0.

To effect rotation of the casing 32 of this modifled valve for the purposes previously described, there is provided at the driving position a hand lever ill and locking quadrant 82.

The lever al is connected by a rod 83 with a tubular spring box 24 from which extends a spring 85 into engagement with an arm St secured to the valve casing 62.

In the arrangement shown in the pilot wheel 43 is connected to the rotary valve 63 by pivoted arms and operates the latter in the manner previously described herein, while rotation and location of the casing 62 about the rotary valve for the purposes described is effected by the hand lever 8|.

To enable the inclination of the rotary broom 22 to be adjusted during travel to conform with transverse sloping surfaces, such as gutters, the broom is adjusted by partial rotation of the gear box 20, as previously described herein.

For the purpose of thus adjusting the gear box and broom, an arm 87 is secured to the former and is connected by a link slidable in a guide 85 pivotally supported on a lug to an encased flexible shaft or cable SI which extends to a manually operable control whereby the cal, e may be actuated longitudinally to operate the arm 81 and thereby angularly adjust the gear box to set the broom 22 at the required in clination.

The rotation of the broom together with the action of gravity result-a tly of the position of the centre of gravity of the broom assembly, causes the broom in traversing a roadway to move laterally outwards from the machine. such movement being permitted by angular movement of the arms I2 and H.

To limit the extent of the outward movement and to retract the broom inwardly towards the machine, there are provided manually operable means at the drivers position, which may com" prise a hand winch (not shown) connected as by a chain 93 to a lug S4 welded to the arm 52.

Alternatively, an appropriate linkage may be connected to the lug 94 and to a manually actuated lever at the drivers position.

It will be apparent that the broom 22 is elevated by the booster 52, but gravitates into en.- gagement with the surface to be swept upon the vacuum in the upper chamber of the latter being broken down.

Such a method is satisfactory when the broom is moving upon a horizontal surface or a transversely sloping surface of moderate inclination, but when the broom is required to sweep a steeply inclined or vertical surface gravity cannot be used to thrust the broom upon the surface.

It then becomes necessary to hold the broom in contact with the surface by mechanical means, which is readily accomplished by employing a double-acting booster, i. e. a booster in which a vacuum may be created in either chamber as required.

To operate such a booster a modified control valve is required, and is illustrated by r-g. 6. In this control valve the rotary valve 63 is actuated by the pilot wheel 43 for angular movement in the casing 62, as previously described.

The casing 62 has a. vacuum port 64, an atmospheric port or passage I2, and a pair of service ports 66 connected respectively to the two chambers of the booster.

In the periphery of the rotary valve there are two grooves 68 which are separated by integral longitudinal portions or bars which as shown are closing the service ports 66.

It will be apparent that the upper groove 68 is connected by the port 64 with the source of vacuum, while the lower groove 68 is in constant communication with the atmosphere.

It will be evident that partial rotation of the rotary valve by the pilot wheel in either direction will connect one service port with the vacuum source and the other service port with the atmosphere, thereby creating a vacuum in one of the booster chambers and placing the other chamber in communication with the atmosphere, the broom 22 being moved accordingly,

Similar action will result from rotation of the casing 62 about the rotary valve as will be readily understood.

If it be necessary or desirable to utilize a reciprocatory valve in lieu of the rotary type of valve described for the double acting booster, the piston valv illustrated by Fig. 7 may be used.

This valve comprises a cylindrical casing 96 having therein a valve 91 comprising a piston 98 slidably fitting the bore of the casing 96, and stems 99 integral with the piston and slidably fitting bores I89 in the cylinder ends IOI, one at least of which is detachable.

A vacuum port 64 is provided at the middle length of the casing 96, and service ports 66 therein and on opposite sides of the piston 98 communicate respectively with the chambers of the booster.

Atmospheric ports I02 are provided in the ends II, and are closed by the stems 99 while the piston 98 shuts off the vacuum port 64, as shown.

Longitudinal movement of the valve 91, as by the pilot wheel, in either direction displaces the piston 98 so as to connect one of the service ports 66 with the vacuum port 64 and the other service port with the atmosphere by way of the port I III and the reduced part or peripheral groove I03 in the valve stem 99.

Similar connection of the service ports with the vacuum port and with the atmosphere can be effected by longitudinal movement of the casing 96 by manual control, as will be readily understood.

A rotary broom constructed and operated as herein described may be used at each side of a road sweeping machine, and a rotary cylindrical broom may be interposed between the two side brooms. The cylindrical broom is adapted to collect and direct the sweepings thrown inwardly by the side brooms upon an elevator or conveyor whereby the sweepings are carried to a receptacle on the machine.

The cylindrical broom is raised and lowered by a booster under control of a pilot member similarly to the side brooms, but the pilot member comprises a skid sliding upon the roadway in lieu of the caster wheel previously described and illustrated.

To provide more effective and quicker movements of the broom, the interior of one or both tubular arms, ich is of considerable volume. may comprise an evacuated space in constant connection with the source of vacuum, and the vacuum port of the control valve may be connected to the evacuated space by a short tube instead of by a long pipe or conduit to the source of vacuum, which usually comprises the inducaeeaeve 9 t'ion manifold of the internal combustionengine whereby the machineis operated.

The tubular arms, when used con-jointly'to prvide the evacuated space, areconn'ected by a flexibletube to providefor' the relative angular movements thereof.

I claim:

1, A mobile apparatus for cleaning roadways and the like, comprising a frame, an angularly adjustable articulated structure dependingfrom said frame, a road cleaning element supported by the articulated structure and movable relatively to a roadway responsive to angular adjustmentsof the articulated structure, pilot means for road engagement located in advanceof the cleaning element in traversing the roadway and supported for rising and falling movements to follow the: surface contour and pass over obstructions, con--- trol means operated by" the pilot means as the latter rises and falls, and operating means respon-- sive to actions of the control means toangularly adjust the articulated structure and thereby elevate and lower the cleaning element in conformity with the rising and falling movements of the pilot means. I

2. A mobile apparatus for cleaning roadways and the like, comprising a frame, a pair of articulated members jointed-1y connected for angular movement, one of the articulated members pendulously supported on said frame of the apparatus and the other of said members extended laterally from the lower end of the pendulously supported member, a road cleaning element carried at the end of the laterally extended memher and movable downwardly and upwardly in relation to the surface of a roadway responsive to relative angular movements of th articulated members, a pilot member for road engagement positioned in advance of the rotary broom in traversing the roadway and pivotally connected to the laterally extended member for rising and falling movements to follow the surface contour and pass over obstructions, control means opera-- tively' connected with the pilot member and actuated by rising and falling movements of said member, and power motivated means interconnecting the articulated members and operable responsive to operation of the control means by the pilot member to angularly move the laterally extended member and elevate and lower the cleaning element in conformitywith the rising and falling movements of. the pilot member.

3. A mobile apparatus for cleaning roadways and the like comprising a frame, two angularly movable arms, one of the arms pivotally supported on and depending from said frame of the apparatus and the other arm pivotally connected to and outwardly extended from the lower end of the depending arm, a road cleaning elementit/ carried by the latter arm, lifting'means interconmeeting the arms and operable to support and raise and lower the outwardly extended arm and the road cleaning element, a pilot member for road engagement propelled in advance of the road cleaning element. and mounted for rising and falling movements in traversing a roadway, and control means for the lifting means operatively connected with the pilot member and 0perable responsive to the rising and falling move ,ments of said member to activate the lifting means to synchronously raise and lower the outwardly extended arm and cleaning element.

4. A mobile road cleaning apparatus, comprising a frame, a pair of coplanar arms connected for relative angular movement, one of the arms pivoted upon and depending from said frame of: the apparatus. and the other ofsaid arms pivotally connected to and outwardly extended from: the lower end of the depending arm, a road cleaning element supported on free end of the latter arm, a fluid actuated lifting motor interposed betweenthe arms andoperable: to support and: raise and lower the outwardly extended arm and the road cleaning element, a. pilot wheel for roadengagement propelled advance of the road cleaning element and pivotally connected to outwardly extended arm for rising and falling movements in traversing" a roadway, and valvular control means operatively connected with the pilot wheel and operable responsive to the rising and falling movements of said wheel to activate said motor to synchronously elevate and lower: the outwardly extended; arm" and cleaning element;

5 A mobile road cleaning apparatus; comprising v a; frame, a member pendulously' supported. on. said. frame of the apparatus, a member pivoted upon. the lower end. of the pendulously supported member, a rotary cleaning element supported on v the free: end of the latter member, motive means on said frame, power transmission means driving.- ly' connecting the motive means and the rotary cleaning element, lifting. means operable to support and angularly raise and lower the pivoted member and the rotary cleaning. element, road engaging pilot means propelled in advance of the rotary cleaning element and supported for rising and. falling movements in traversing a mad way, and control means operatively connected with the pilot means and operable responsive to rising and falling movements of said pilot means to activate the lifting means to. synchronously elevate and lower the pivoted member andthe rotary cleaning element;

6 A mobile road cleaning apparatus comprising a frame,- an elongated. pendant member pivotally connected to said frame of the apparatus, a horizontally disposed member pivotally connected to the lower end of. the pendant member, a rotary broom mounted for rotation on the free end of the horizontally disposed member, a power unit on said frame, power transmission means supported by the pendant member andv the hortzontally disposed members and drive connecting the power' unit with therotary broom, a power operated lifting means operable to "support and angularly raiseandlower the pivotally connected member and the rotary broom, a road engaging pilot wheel propelled inadvance of the rotary broom and pivotally supported to'ri'se' and fall in traversing the surface of a roadway,and control means operatively connected with thepilot wheel and operable responsive to rising and. falling movements of said wheel to synchronously elevate and lower the horizontally disposed mem 0 her and the rotary broom.

7. A mobile road cleaning apparatus comprismg a frame, a pair. of coplanar. arms connected end' to end for relative angular movement, one of the arms pivoted upon and depending from said frame of the apparatus and the other of said arms pivotally connected to and projecting from the lower end of the depending arm, a rotary broom mounted for rotation on the free end of the pro ecting arm and pivotally supported for angular movement in the common plane of said arms a power unit on said frame, power transmission means carried by the coplanar arms and drive connecting the power unit with the rotary broom, fluid actuated lifting means interposed between and connected to said arms and operable to support and angularly raise and lower the projecting arm and the rotary broom, a pilot road engaging wheel propelled in advance of the rotary broom and pivotally connected to the projecting arm for rising and falling movements in traversing a roadway, and valvular control means operatively connected with the pilot wheel and operable responsive to rising and falling movements of said wheel to activate the fluid actuated lifting means to synchronously elevate and lower the projecting arm and the rotary broom.

8. A mobile road cleaning apparatus, comprising a frame, a depending primary arm carried by a pivotal support on said frame of the apparatus, a secondary arm coplanar with the primary arm mounted upon a pivotal support carried by the latter arm, a gear box pivotally supported at the end of the secondary arm, an output shaft projecting from the gear box and carrying a rotary broom, a power unit on the frame of the apparatus, a driving shaft rotatably mounted in the pivotal support of the primary arm and drive connected with the power unit, a driven shaft rotatably mounted in the pivotal support of the projecting arm, sprocket and chain transmission connecting the driving shaft with the driven shaft, an input shaft rotatably mounted in and projecting from the gear box, gearing in the gear box drive-connecting the input shaft with the output shaft, sprocket and chain transmission connecting the driven shaft with the input shaft, a pneumatic lifting motor connecting the primary arm with the secondary arm and operable to support and angularly raise and lower the latter arm and the rotary broom, a road engaging pilot wheel propelled in advance of the rotary broom and pivotally connected to the secondary arm for rising and falling movements in traversing a roadway, and a control valve operatively connected with the pilot wheel and operable by said wheel in rising and falling to activate the lifting motor to synchronously elevate and lower the secondary arm and the rotary broom.

9. A mobile road cleaning apparatus as claimed in claim 8, and having the gear box pivotally supported upon an axis substantially parallel with the direction of travel of the apparatus in trav rsing a roadway, and having means for angularhkmoving the gear box and the rotary broom about -the axis of a plane transversely disposed to the direc tion of travel of the apparatus.

10. An apparatus as claim d in claim 8, wherein the pivotal supports of the pr ary and secondary arms comprise spaced support bearing housing secured to the arm and positioned between the spaced supports, coaxially alig aperture in the spaced supports, conical bearing members adjustably rotatable in the coaxially aligned apertures and projecting axially into the bearing housing, complementary tapered bearing members secured in the bearing housing and engaged by the conical bearing members,

eccentric coaxially aligned bearings in the coni- 65 9 12 cal bearing members adjustably supporting the driving or the driven shaft, means for detachably fixing the conical bearing members to the spaced supports, and means for axially adjusting the conical bearing members into engagement with the tapered bearing members.

11. An apparatus as claimed in claim 8, and having a control valve comprising a casing, a rotary valvular member fitting within the casing and operatively connected with the pilot wheel for angular movements in the casing responsive to rising and falling movements of said wheel, a vacuum port in the casing connected with a source of vacuum, a service port in the casing connected with the pneumatic motor, a passage in the rotary valvular member open to atmosphere, an arcuate groove in the periphery of the rotary valvular element to connect the vacuum port with the service port, a recess in the periphery of the rotary valvular member, a valve block in the peripheral recess, a groove in the valve block to connect the service port with said passage, 21. bar on the valve block separating the groove in said block from the arcuate groove, and manually actuated means connected to the casing and operable to angularly move the casing about the rotary valvular member.

12. An apparatus as claimed in claim 8, wherein the pilot wheel is pivotally connected to the primary arm by a parallel motion frame whereby said wheel in rising and falling moves in a rectilinear vertical course, and one of the members of said frame being operatively connected to the control valve.

13. A mobile apparatus for cleaning roadways and the like, comprising a frame, an angularly adjustable structure depending from said frame, a road cleaning element supported by the structure and movable relatively to a roadway responsive to angular adjustments of the structure, pilot means for road engagement located in advance of the cleaning element in traversing the roadway and supported for rising and falling movements to follow the surface contour and pass over obstructions, control means operated by the pilot means as the latter rises and falls, and operating means responsive to actions of the control means to angularly adjust the structure and thereby elevate and lower the cleaning element in conformity with the rising and falling movements of the pilot means.

HEDLEY BENJAMIN KEOGH.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 524,875 Tobey Aug. 21, 1894 $991,647 Howald Mar, 14, 1933 2,236,817 Evans Apr. 1, 1941 2,278,306\C ushman Mar. 31, 1942 2,343,227 SeIlers\ Feb, 29, 1944 2,513,587 Reeves July 4, 1950 Reeves Oct. 17, 1950 

